drivers/net/ethernet/netronome/nfp/nfp_hwmon.c

// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/* Copyright (C) 2017 Netronome Systems, Inc. */

#include <linux/kernel.h>
#include <linux/bitops.h>
#include <linux/hwmon.h>

#include "nfpcore/nfp_cpp.h"
#include "nfpcore/nfp_nsp.h"
#include "nfp_main.h"

#define NFP_TEMP_MAX		(95 * 1000)
#define NFP_TEMP_CRIT		(105 * 1000)

#define NFP_POWER_MAX		(25 * 1000 * 1000)

static int nfp_hwmon_sensor_id(enum hwmon_sensor_types type, int channel)
{
	if (type == hwmon_temp)
		return NFP_SENSOR_CHIP_TEMPERATURE;
	if (type == hwmon_power)
		return NFP_SENSOR_ASSEMBLY_POWER + channel;
	return -EINVAL;
}

static int
nfp_hwmon_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
	       int channel, long *val)
{
	static const struct {
		enum hwmon_sensor_types type;
		u32 attr;
		long val;
	} const_vals[] = {
		{ hwmon_temp,	hwmon_temp_max,		NFP_TEMP_MAX },
		{ hwmon_temp,	hwmon_temp_crit,	NFP_TEMP_CRIT },
		{ hwmon_power,	hwmon_power_max,	NFP_POWER_MAX },
	};
	struct nfp_pf *pf = dev_get_drvdata(dev);
	enum nfp_nsp_sensor_id id;
	int err, i;

	for (i = 0; i < ARRAY_SIZE(const_vals); i++)
		if (const_vals[i].type == type && const_vals[i].attr == attr) {
			*val = const_vals[i].val;
			return 0;
		}

	err = nfp_hwmon_sensor_id(type, channel);
	if (err < 0)
		return err;
	id = err;

	if (!(pf->nspi->sensor_mask & BIT(id)))
		return -EOPNOTSUPP;

	if (type == hwmon_temp && attr == hwmon_temp_input)
		return nfp_hwmon_read_sensor(pf->cpp, id, val);
	if (type == hwmon_power && attr == hwmon_power_input)
		return nfp_hwmon_read_sensor(pf->cpp, id, val);

	return -EINVAL;
}

static umode_t
nfp_hwmon_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr,
		     int channel)
{
	if (type == hwmon_temp) {
		switch (attr) {
		case hwmon_temp_input:
		case hwmon_temp_crit:
		case hwmon_temp_max:
			return 0444;
		}
	} else if (type == hwmon_power) {
		switch (attr) {
		case hwmon_power_input:
		case hwmon_power_max:
			return 0444;
		}
	}
	return 0;
}

static u32 nfp_chip_config[] = {
	HWMON_C_REGISTER_TZ,
	0
};

static const struct hwmon_channel_info nfp_chip = {
	.type = hwmon_chip,
	.config = nfp_chip_config,
};

static u32 nfp_temp_config[] = {
	HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_CRIT,
	0
};

static const struct hwmon_channel_info nfp_temp = {
	.type = hwmon_temp,
	.config = nfp_temp_config,
};

static u32 nfp_power_config[] = {
	HWMON_P_INPUT | HWMON_P_MAX,
	HWMON_P_INPUT,
	HWMON_P_INPUT,
	0
};

static const struct hwmon_channel_info nfp_power = {
	.type = hwmon_power,
	.config = nfp_power_config,
};

static const struct hwmon_channel_info * const nfp_hwmon_info[] = {
	&nfp_chip,
	&nfp_temp,
	&nfp_power,
	NULL
};

static const struct hwmon_ops nfp_hwmon_ops = {
	.is_visible = nfp_hwmon_is_visible,
	.read = nfp_hwmon_read,
};

static const struct hwmon_chip_info nfp_chip_info = {
	.ops = &nfp_hwmon_ops,
	.info = nfp_hwmon_info,
};

int nfp_hwmon_register(struct nfp_pf *pf)
{
	if (!IS_REACHABLE(CONFIG_HWMON))
		return 0;

	if (!pf->nspi) {
		nfp_warn(pf->cpp, "not registering HWMON (no NSP info)\n");
		return 0;
	}
	if (!pf->nspi->sensor_mask) {
		nfp_info(pf->cpp,
			 "not registering HWMON (NSP doesn't report sensors)\n");
		return 0;
	}

	pf->hwmon_dev = hwmon_device_register_with_info(&pf->pdev->dev, "nfp",
							pf, &nfp_chip_info,
							NULL);
	return PTR_ERR_OR_ZERO(pf->hwmon_dev);
}

void nfp_hwmon_unregister(struct nfp_pf *pf)
{
	if (!IS_REACHABLE(CONFIG_HWMON) || !pf->hwmon_dev)
		return;

	hwmon_device_unregister(pf->hwmon_dev);
}